Dear Editor, Children with COVID-19 infection can present with a variable spectrum of clinical manifestations, and sometimes mucocutaneous manifestations can be the only manifestation of COVID-19 infection in children.1,2,3 We report 4 cases of paediatric patients who had COVID-19 with mucocutaneous involvement, admitted to a tertiary children’s hospital in Singapore....

An 84-year-old Chinese man with stage IV non-small cell lung cancer was initiated on pembrolizumab, an anti-programmed cell death (PD)-1 monoclonal antibody, 4 times per week. Seven weeks later, on the day of his third cycle, he developed a rash on his chest and right axilla, which subsequently resolved...

A 65-year-old Chinese man was admitted for evaluation of chronic anaemia. He had a history of hypertension and chronic kidney disease, and his regular medications were nifedipine and losartan. He was a retired cleaner who lived with friends and had no contact with his family. He was referred to the...

An 81-year-old woman of healthy weight presented with a 2-week history of a painless right axillary lump. Physical examination revealed a 2cm firm nodule with a central keratinous plug in the right axilla (Fig. 1). The surrounding skin was pigmented, non-tender and indurated. Sonography of the nodule demonstrated an...

Dear Editor, Hepatitis B virus (HBV) infection poses a global health burden. Clinically, patients may present with chronic HBV infection, occult HBV infection, and fulminant hepatic failure. In 2010, the hepatitis B surface antigen (HBsAg) seroprevalence in Singapore was 3.6%.1 Patients with dermatological conditions receive prolonged corticosteroid and other immunosuppressive therapy...

Cutaneous polyarteritis nodosa (CPN) is an uncommon form of vasculitis of the small-and medium-sized arteries in the reticular dermis and subcutaneous tissue. It remains limited and runs a chronic, benign course. This article is available only as a PDF. Please click on “Download PDF” on top to view the full...

Our patient is a 64-year-old Malay man who first presented in July 1993 with a history of rash starting on the hands 1½ years earlier progressing to generalised eczema 5 months prior to consultation. He was diagnosed to have generalised exfoliative dermatitis (GED). This article is available only as a...

Neutrophilic eccrine hidradenitis (NEH) is a neutrophilic dermatosis primarily affecting the eccrine glands and occurs most commonly in patients undergoing chemotherapy for a malignancy. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

In 1969, Rosai and Dorfman first described a newly recognised benign systemic histioproliferative disease characterised clinically by bilateral striking cervical lymphadenopathy, fever, leukocytosis, and pathologically by enlarged lymph nodal sinuses containing large histiocytes with intact phagocytosed lymphocytes (emperipolesis). They dubbed the entity “sinus histiocytosis with massive lymphadenopathy” (SHML or...

Bullous dermatomyositis is a rare variant of dermatomyositis and has been reported in the literature. It is believed to be strongly associated with the presence of a malignancy. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Linear IgA bullous dermatosis of childhood (LADC) is an acquired subepidermal blistering disorder of young children which is characterised by the unique finding of linear deposits of IgA along the dermoepidermal junction. It usually occurs acutely in pre-school children and has been described in association with a variety of...

Mycobacteria other than tubercle bacilli (MOTT) were shown to be agents of human disease in the 1950s. They are also known as atypical, environmental or opportunistic mycobacteria. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Pityriasis rosea is a common, self-limited disorder of unknown but suspected viral aetiology, that develops abruptly with few or no prodromal symptoms. Classically, the first sign is the presence of a single lesion, 2 to 5 cm in diameter known as a “herald patch”. This article is available only as...

Treatment of vitiligo can sometimes be difficult and disappointing. Medical treatment includes topical or systemic steroids and psoralen with ultraviolet A light (PUVA). This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Porocarcinoma is a rare malignant tumour, arising from the intra-epidermal ductal portion of the eccrine sweat gland, also known as “acrosyringium”.’ According to the histological typing of skin tumours, it is an eccrine carcinoma that may arise de nova or develop in eccrine poroma, its benign counterpart, as an...

Behcet’s disease, first described by a Turkish dermatologist, Dr Hulusi Behcet, is a multisystem inflammatory disorder of unknown aetiology. The diagnosis of Behcet’s disease is based on clinical criteria because there are no pathognomonic laboratory features. This article is available only as a PDF. Please click on “Download PDF” on...

Infections caused by Chlamydia trachomatis are amongst the most common bacterial sexually transmitted diseases (STDs) in the world, causing substantial morbidity in young sexually-active people. C. trachomatis causes a variety of clinical syndromes in males (including urethritis and epididymitis), females (including cervicitis and pelvic inflammatory disease), and new-borns (including...

A 70-year-old Chinese man with end-stage renal failure (ESRF), who has been on continuous ambulatory peritoneal dialysis for 6 months, was referred by the renal physician for pruritic rashes over the scalp and chest. The rashes were first noted about 3 months ago. This article is available only as a...

Epidermal cysts are common benign subcutaneous lesions. Malignant transformation in epidermal cysts is a rare but recognised occurrence. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Granuloma annulare (GA) is a benign, inflammatory disorder of the skin that has no proven aetiology or widely accepted theory of pathogenesis. There are several clinical manifestations, ranging from localised GA, which is the commonest form and is characterised by erythematous or flesh-coloured papules in an annular arrangement, to...

There are many dermatological manifestations of tuberculosis, ranging from distinct entities such as tuberculosis verrucosa cutis, lupus vulgaris, scrofuloderma, to tuberculides. The term tuberculide is applied to any of a group of eruptions which arise in response to an internal focus of tuberculosis and clear with anti-tuberculosis therapy. This article...

I refer to a paper published in the Annals Vol. 28 No. 6 November 1999 titled “One-year review of pityriasis rosea at the National Skin Centre, Singapore” by Drs Y K Tay and C L Goh. I would like to point out that a prospective study on pityriasis rosea...

Chronic urticaria is defined as daily outbreaks of urticaria of at least 6 weeks duration. Despite being a common disorder, the cause of chronic urticaria is often obscure and not easily treatable. This article is available only as a PDF. Please click on “Download PDF” on top to view the...

A 49-year-old Chinese man presented at the Tan Tock Seng Hospital with painful gangrene of the right second and left third and fourth toes for 6 weeks, purple discolouration of the toes for 3 months and arthritis of the left knee for 3 months. This article is available only as...

Polymyositis/dermatomyositis is a connective tissue disorder with inflammatory muscle disease resulting in muscle weakness. When there is only muscle involvement, the term polymyositis is used. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Neonatal lupus erythematosus (NLE) is related to the transplacental passage of anti-Ro antibodies from mother to foetus. The commonest manifestations involve the skin and the heart. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Systemic amyloidosis, first reported in 1886, is characterised by deposits of amyloid in various organs including the skin, which may manifest as skin purpura, papules, nodules and occasionally bullae (termed bullous amyloidosis in the literature), predominantly distributed over the periorbital and intertriginous areas. In contrast, lichen amyloidosus is solely...

Dear Editor, Atopic dermatitis (AD) is a chronic inflammatory skin disease, affecting approximately 20% of children in Singapore.1 It is associated with skin barrier defects2 and increased skin colonisation with Staphylococcus aureus, which can trigger infective flares, especially in more severe disease. Strategies to reduce S. aureus colonisation and infection...

A 40-year-old Chinese man of skin phototype III (Table I), formerly a welder in a shipyard, presented with pruritic papules on his face, neck and arms of 3 years’ duration. He had noted sun-aggravation and had ceased working for 3 months. This article is available only as a PDF. Please...

Allergic contact dermatitis is a common clinical problem seen in our dermatology outpatient clinics, comprising 0.5% of patients seen in 1999. In addition to our contact dermatitis clinic and occupational dermatosis clinic which caters to subsidised patients, many patients have also been worked up and patch tested in the...

Unlike in Caucasians, primary malignant melanoma is an uncommon skin malignancy in Singapore. There have been little published data on cutaneous melanoma in Southeast Asia. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Incontinentia pigmenti, called Bloch-Sulzberger syndrome, is a rare X-linked dominant disorder involving ectodermal structures. It is a multisystem disorder with cutaneous, ocular, dental, cerebral and skeletal manifestations. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Melanocytic naevi are benign proliferation of melanocytes of congenital and acquired types which usually appear during adolescence or early adult life. Naevi are of three common subtypes i.e. junctional, compound and intradermal melanocytic naevi, with characteristic clinical appearance that aids in clinical diagnosis. This article is available only as a...

In Southeast Asia, there have been few studies on the emergence of antibiotic-resistant strains of Propionibacterium acnes on the skin of patients with acne vulgaris. We previously reported the effect of short courses of antibiotics on the minimum inhibitory concentrations (MICs) of P. acnes. This article is available only as...

Laboratory confirmation of cutaneous tuberculosis has remained difficult using conventional techniques which include the demonstration of acid-fast bacilli (AFB) on histopathologic examination and culture. In tuberculosis verrucosa cutis and lupus vulgaris which are paucibacillary, direct microscopy and tissue cultures lack the specificity and/or sensitivity for the detection of Mycobacterium...

Androgenetic alopecia is hair thinning or balding due to the influence of androgens in males and females. Androgenetic alopecia is reported to affect 50% of the population by the age of 50 years in males and a decade later in females. This article is available only as a PDF. Please...

BCG vaccines are live vaccines derived from a strain of Mycobacterium bovis that was attenuated by Calmette and Guerin at the Pasteur Institute in Lille, France. In Singapore, all newborn babies are given the vaccination at birth, and until recently, a second vaccination was given to children at the...

Anogenital warts are caused by specific subtypes of the human papillomavirus (HPV), of which serotypes HPV 6 and 11 are the most common. There are 3 types of HPV infection: This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Sexually transmitted diseases (STDs) in persons older than 50 years are rarely studied because STDs are more common in young people. There is very little published data focussing on this group of patients which is relevant to Singapore or this part of the world. This article is available only as...

Allopurinol hypersensitivity syndrome is an idiosyncratic drug reaction characterised by an acute and severe multiorgan disease. It usually begins 2 to 6 weeks (up to 3 months) after starting allopurinol. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Bullous pemphigoid (BP) is an autoimmune subepidermal blistering disorder affecting mainly the elderly. It is characterised by autoantibodies to the basement membrane zone (BMZ), which are detectable on immunofluorescent studies. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Livedoid vasculitis is a clinicopathological entity that has variously been referred to as atrophie blanche, livedoid vasculopathy or segmental hyalinising vasculitis. It presents with purpuric lesions and recurrent, painful ulcerations of the lower limbs which result in depressed, atrophic white scars. This article is available only as a PDF. Please...

Sweet’s syndrome is an acute febrile neutrophilic dermatosis. An association with malignancy is well recognised. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

A 64-year-old man presented to the dermatology outpatient clinic with a 4-month history of pruritic papules. He had a significant medical history of thyrotoxicosis, which was diagnosed 1 year prior and well controlled on carbimazole. He had no history of dyslipidaemia or underlying malignancy. The cutaneous eruption had first...

Autoimmune blistering conditions are an uncommon cause of chronic ulceration of the oral mucosa. Nevertheless, it is important to diagnose these conditions early and institute treatment as soon as possible, as they can lead to serious involvement in other mucosal and cutaneous sites and even death. This article is available...

Cutaneous melanocytic lesions are amongst the commonest tumours in all races but are more common in Caucasians with fair skin. Although most are benign melanocytic naevi that are readily diagnosed clinically, melanocytic lesions are commonly excised because of the concern that they may represent a melanoma or because of...

Recurrent erythema multiforme (EM) is a disabling condition with a specific diagnosis and certain diagnostic criteria. Systemic corticosteroid therapy is frequently used to treat this condition. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

There have been significant advances in the understanding of keratinocyte stem cells since the 1970s, when the concept of interfollicular epidermis was initially proposed; later much work was focused on the specific region of the hair follicle outer root sheath, especially the bulge region (Fig. 1). Hair follicle stem...

Behçet’s disease (BD) is characterised by oral aphthous lesions, genital ulcerations and eye inflammation. The disease was first described by Hulusi Behçet in 1937. Despite the diverse inflictions in different organ systems, vasculitis is perceived as the common basic pathological process in BD. This article is available only as a...

Mycobacterium haemophilum is a nontuberculous mycobacterium (NTM) that is increasingly recognised as a cause of cutaneous, joint, or pulmonary infections in immunocompromised patients and lymphadenitis in children. To date, less than 100 patients with this infection have been reported worldwide. This article is available only as a PDF. Please click...

Nephrogenic fibrosing dermopathy (NFD) is a recently described and recognised fibrosing disorder occurring in patients with renal disease. The condition resembles scleromyxoedema clinically and histologically, and was originally termed “scleromyxoedema-like illness of haemodialysis”. This article is available only as a PDF. Please click on “Download PDF” on top to view...

Dapsone hypersensitivity syndrome (DHS) is a rare condition mostly occurring in leprosy patients on multidrug therapy. Dapsone is also combined with pyrimethamine as maloprim (Beacons Chemicals Pte Ltd, Singapore), a fairly effective chemoprophylactic agent in the management of malaria. This article is available only as a PDF. Please click on...

Cyclosporin is a potent immunosuppressant that inhibits cell-mediated immunity, mainly via inhibition of T helper cells. It has been used successfully in the treatment of severe atopic dermatitis in children and adults, producing a rapid and highly significant improvement in terms of disease activity, pruritus and sleep disturbance. This article...

The pathophysiological mechanisms in psoriasis are still unclear. Many factors, such as infection, trauma and stress, could cause psoriasis. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Lymphomatoid papulosis is a self-healing recurrent popular eruption often exhibiting a chronic course. It is associated with malignant lymphomas in 10% to 20% of cases. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Calcinosis cutis is characterised by the aberrant deposition of calcium salts in the skin. In metastatic calcinosis cutis, calcium salts are precipitated in normal tissue as a result of an underlying defect in calcium and/or phosphate metabolism. This article is available only as a PDF. Please click on “Download PDF”...

Delusional parasitosis (DP), or delusional infestation, is a condition in which a person has the unshakeable and mistaken belief of being infested with parasites. Originally described in 1894, it has been previously referred to as dermatophobia, parasitophobic neurodermatitis, parasitophobia or entomorphobia. This article is available only as a PDF. Please...

Non-invasive techniques have become useful procedures in measuring skin physiology and skin response to treatment. This study attempts to objectively measure physiological changes in transepidermal water loss (TEWL), an indicator of skin barrier function, and laser Doppler perfusion imaging (LDPI), an indicator of dermal vascularity, of psoriatic skin lesions...

Family history has been shown to be a risk factor for the development of allergic rhinitis (AR) and atopic dermatitis (AD). However, the increase in prevalence has also been attributed to the changes in lifestyle and urbanisation in developed countries. This article is available only as a PDF. Please click...

Non-melanoma skin cancer is the most common skin cancer worldwide and its incidence has risen in the last few decades. Approximately 80% of non-melanoma skin cancers are basal cell carcinomas and the rest are squamous cell carcinomas (SCCs). This article is available only as a PDF. Please click on “Download...

Viral warts are a common affliction in children. It is caused by the human papilloma virus, of which there are more than 80 serotypes. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

A 22-year-old Malay soldier doing his National Service was warded with a 6-day history of an itchy generalised rash associated with fever and lymphadenopathy. Prior to this episode, he was well and not known to have any major illnesses. This article is available only as a PDF. Please click on...

Atopic dermatitis (AD) is a chronic and pruritic inflammatory skin disorder that occurs worldwide. Several guidelines on the management of AD have been published in the literature. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

A 74-year-old Chinese woman presented with a 1-week history of an itchy rash on the trunk and legs. A barium enema was performed a day before the rash started. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Antimonial compounds are regarded as the treatment of choice for cutaneous leishmaniasis (CL). The efficacy of sodium stibogluconate (pentostam) and the other compound of antimoniate meglumine antimoniate (glucantime) were reported in 1937 and 1946, respectively. This article is available only as a PDF. Please click on “Download PDF” on top...

Leishmaniasis is a parasitic infection caused by different species of the obligate intracellular protozoa Leishmania. This disease is transmitted through the bite of an infected female sandfly. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

Cutaneous T-cell lymphomas (CTCL) are a heterogeneous group of malignancies of skin-homing T-cells, of which mycosis fungoides (MF) is the most common form. CTCL can be difficult to diagnose, especially in the early stages or in cases with atypical clinical presentation. This article is available only as a PDF. Please...

Dear Editor, Mohs micrographic surgery (MMS) has become the treatment of choice for high-risk non-melanoma skin cancers (NMSC) worldwide.1 Unlike wide local excision, MMS enables precise microscopic removal of tumour foci while allowing maximal tissue preservation, thereby maintaining cosmesis and anatomical function.1 The MMS service in Singapore started in...

Dear Editor, With the advancements in pharmacogenetics, potential genetic associations with severe cutaneous adverse drug reactions (SCAR)—which include Stevens- Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN)—have been proposed. Lamotrigine is one of the 2 anticonvulsants found to be highly associated with SJS/TEN from the 2008 EuroSCAR study. Several...

Angiosarcoma is a rare tumour commonly affecting elderly men, usually occurring on the head and neck region. The tumour usually presents as ecchymosis-like plaques, and less commonly with haemorrhage, oedema, ulceration and recurrent facial angioedema. This article is available only as a PDF. Please click on “Download PDF” on top...

Various types of skin lesions are more common in renal transplant recipients compared to the general population, mainly attributable to post-transplant immunosuppression. The well-documented drug-specific skin manifestations include cyclosporine-related hypertrichosis, gingival hypertrophy, steroid-induced acneiform eruption and striae. This article is available only as a PDF. Please click on “Download PDF”...

Bosentan is an endothelin-1 (ET-1) receptor antagonist approved for the treatment of pulmonary artery hypertension (PAH). Although flushing is a documented side effect of bosentan, the diagnosis can mimic other drug rashes and medical conditions where facial telangiectasis and/or flushing are prominent presentation. This article is available only as a...

A 96-year-old woman was referred as an emergency with a suspected allergic reaction to Deep Heat® rub (Mentholatum Company Ltd, East Kilbride, Scotland). Five days before referral, she developed pain and stiffness of her left neck and shoulder. This article is available only as a PDF. Please click on “Download...

Dermatomyositis (DM) is an acquired multisystem inflammatory disease with prominent, characteristic cutaneous manifestations and proximal muscle myopathy. A clinically distinct amyopathic variant with typical skin signs but no muscle disease had been described as well. This article is available only as a PDF. Please click on “Download PDF” on top...

A 2-year-old Chinese girl was seen in clinic with an erythematous annular itchy rash which began on the thighs and had spread to the trunk and hands. The parent’s concern was the rash’s duration and association with 2 episodes of fever. This article is available only as a PDF. Please...

Toxic Epidermal Necrolysis (TEN) is a rare, fulminating rash with a mortality rate of 35%.1 It is predominantly medication-induced; allopurinol, ampicillins, anticonvulsants and non-steroidal anti-inflammatory drugs are commonly implicated. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

In the last decade, our understanding of psoriasis has increased by leaps and bounds, resulting in many new targeted therapies being introduced for those with recalcitrant psoriasis. However, despite the plethora of new treatment options and biologics to treat the most difficult cases of psoriasis, dermatologists are still confronted...

Three years after emigrating from Philippines to Singapore, a 34-year-old, otherwise healthy man presented with a progressive erythematous eruption on his lower limbs. Six months prior to presentation he noticed a few rythematous plaques on his right lower limb, which were gradually increasing in size and later spread to...

Tinea capitis is a fungal infection of the hairs of the scalp. Although commonly described in children, it is uncommonly seen in Singapore. This article is available only as a PDF. Please click on “Download PDF” on top to view the full article.

A 14-year-old, otherwise healthy boy presented with a skin nodule for the past 3 years which slowly lifted up the right fourth fingernail. The lesion was tender to palpation. He denied any previous trauma and there was no family history of similar lesions. This article is available only as a...

A 70-year-old gentleman with a significant past history of using traditional medication presented to our clinic with multiple dysplastic lesions of varying severity on the covered areas of his chest and back and ketatotic lesions on his palms and soles for 2 years. We present 3 clinical photographs and...

A 45-year-old Chinese woman with no medical history or regular medications presented with painful nodules on her left shin that progressed to involve her right shin, thighs and lower back over a period of 3 months. There was associated lower limb joints stiffness. Systemic review revealed constitutional symptoms of...

Skin disorders pose a frequent diagnostic challenge for emergency physicians due to their broad spectrum and varied clinical manifestations. The diagnosis of acute dermatologic diseases may be challenging for junior doctors working in a busy emergency department (ED), many of whom may have inadequate clinical exposure or supervised training...

Pyoderma gangrenosum (PG) is an ulcerative neutrophilic dermatosis of uncertain aetiology. Known associations include inflammatory bowel disease, myeloproliferative disease and various arthritides. There have been 4 published cases of PG following total knee arthroplasty (TKA) This article is available only as a PDF. Please click on “Download PDF” on top...

Bullous pemphigoid (BP) is a subepidermal blistering dermatosis characterised by circulating autoantibodies targeting BP180 and BP230 hemidesmosomal proteins. Anti-BP180 NC16A IgG antibodies have been demonstrated to be directly pathogenic in blister formation. Anti-BP180 IgG titres were noted to parallel disease activity in several case series, as well as reflect...

In 1909, Hyde first described nodular prurigo as pruritic nodules on the extensor surfaces of the lower extremities in middle-aged women. Thus, nodular prurigo is also known as Hyde’s prurigo. As the name suggests, nodular prurigo is a chronic dermatosis characterised by an intensely pruritic, papulonodular eruption. We describe...

A 44-year-old Chinese man presented with a 3-week history of heat intolerance and a reduced ability to sweat even upon strenuous physical exertion. His medical history was significant for HIV infection on treatment with efavirenz and lamivudine/zidovudine. He also had drug reaction with eosinophilia and systemic symptoms (DRESS) to...

A 59-year-old woman with a pre-existing asymptomatic pigmented nevus on the umbilicus for the past 20 years was seen in the outpatient dermatology clinic for a 2-week history of a raised, bleeding pigmented papule overlying the nevus. Physical examination showed a 7 x 7mm ulcerated papule overlying a 2.2...

Recent research in atopic dermatitis (AD) has identified it to be a heterogeneous inflammatory skin disorder of different endotypes (immune polarisation of T-cell subsets and genetic mutations) underlying various phenotypes (age of onset, ethnicity, disease severity, etc.). The corresponding heterogeneity in underlying patho-mechanisms of the disease may explain the...